CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jiaming Li,Zhaoping Chen,Jianming Liu,Enrou Mei,Xiaojuan Liang,Jianping Liu,Weidong Xiang
CsPbX 3 (X = Br, I) quantum dots (QDs) have gradually become the star materials in light-emitting diodes (LED), but its stability has a big impact on development. Here, a variety of novel CsPbX 3 -TS-1 nanocomposites have been fabricated and the luminescence wavelength can be tunable by varying the halide nanocomposites (Br, I). What's particularly nice is that the original photoluminescence quantum yield (PLQY) of CsPbBr 1 l 2 QDs approaches 82% and it still has close to 74% after being combined with TS-1. Besides, the nanocomposites enhance stability resisting moisture, thermal stressing and light. In addition, a 460 nm InGaN blue chip, YAG:Ce 3+ and CsPbBr 1 I 2 -TS-1 were equipped with white light emitting diodes (WLEDs), with a luminous effect of 95 lm/W, a color rendering index of 80, and a color temperature of 5144 K. Meanwhile, wide color gamut (116% of the National Television Standards Committee, 86.3% of the ITU-R Recommendation BT. 2020) and great chromaticity coordinate (0.3425, 0.3408) are realized. This is a very important step to open up the awkward situation of the practical application of perovskite QDs materials in LED.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Yadan Luo,Ying Li,Ning Zhang,Yushi Ding,Hongzheng Li,Gang Chen
The effects of bromine (Br) addition on electrical properties and chemical stability of Gd-doped barium cerate proton-conducting electrolyte were investigated. BaCe 0.8 Gd 0.2 O 2.8±δ Br 0.2 (BCGBr) and BaCe 0.8 Gd 0.2 O 3-α (BCG) powders with CuO as sintering aid were obtained via a solid-state reaction. The results of X-ray fluorescence (XRF) confirm that only trace amounts of Br are present in BCGBr after high temperature sintering at 1600 °C, indicating that Br addition influences stoichiometry but not directly the physicochemical properties. Nevertheless, the XRD results from the treated BCGBr and BCG electrolyte pellets show that the chemical stability of BCGBr in water and/or CO 2 -containing atmospheres is conspicuously improved. The conductivities of electrolyte sintered at 1600 °C for 10 h were investigated in various atmospheres by AC impedance technique. The total conductivity ( σ t o t ) of BCGBr under wet Ar is lower than that of BCG. Partial-conductivities components ((proton ( σ OH O · ), oxygen ion ( σ V O · · ), and hole ( σ h · )) are presented for BCGBr according to the defect structure model. The results show that the proton conductivity of BCGBr remains nearly constant over the 550–750 °C temperature range. Although σ t o t of Br-synthesized sample slightly decreases, the BCGBr exhibits a high σ OH O · (0.058 S cm −1 at 750 °C) under pH 2 O = 0.038 atm and pO 2 = 1 atm. P-type and oxygen ion conduction are dominant in an oxidative atmosphere (pO 2 = 1 atm) at 650 °C. Under low oxygen conditions (pO 2 = 10 −4 atm), BCGBr shows the behavior of mixed conduction (oxygen ions ( V O · · ) and protons ( OH O · )). Besides, the main carriers in BCGBr oxide change from OH O · to V O · · as temperature increased.
研究领域:
材料科学
·
固体化学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 15
·4914-4919
·
IF 4.174
Ting Wang,Yi-Gang Chen,Yao Guo,Fang Wang,Qi Song,Ying-Jie Jia,Xian-Ming Zhang
Isostructural mixed alkali/alkaline-earth metal tellurite halides BaLiTe2O5X (X = Cl, Br) have been successfully synthesized by a mild hydrothermal method, which possess the [Te2O5]∞ chains formed by the corner-sharing connections of the TeO3 and TeO4 polyhedra. The [Te2O5]∞ chains are bridged via the LiO3 polyhedra to form the [LiTe2O5]∞ layers with 4- and 6-membered rings. The adjacent [LiTe2O5]∞ layers are linked via the BaO9 polyhedra to form the [BaLiTe2O5]∞ double layers, which are further connected via weak Ba–X–Li interactions to generate a 3D framework. Analysis of different lithium tellurites shows that the different arrangements of the Te–O and Li–O units in the lithium tellurites can be attributed to the cation–cation repulsion and lone-pair effect. Both compounds display good thermal stability, wide optical bandgaps (4.25 and 4.13 eV), and large birefringence. First-principles calculations indicate that the TeOn groups and X− determine the optical properties of BaLiTe2O5X (X = Cl, Br).
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2021
·Vol. 17
·期 28
·2101403
·
IF 13.281
Qiqian He,Gaoyu Chen,Yongkai Wang,Xiaoyu Liu,Danting Xu,Xiangxing Xu,Ying Liu,Jianchun Bao,Xun Wang
All-Inorganic perovskite CsPbX 3 (X = Cl, Br, I) quantum dots (QDs) have attracted tremendous attention in the past few years for their appealing performance in optoelectronic applications. Major properties of CsPbX 3 QDs include the positive photoconductivity (PPC) and the defect tolerance of the in-band trap states. Here it is reported that when hybridizing CsPbX 3 QDs with indium tin oxide (ITO) nanocrystals to form CsPbX 3 -ITO nano-heterojunctions (NHJs), a voltage tuned photoresponse—from PPC to negative photoconductivity (NPC) transform—is achieved in lateral drain-source structured ITO/CsPbX 3 -ITO-NHJs/ITO devices. A model combining exciton, charge separation, transport, and most critical the voltage driven electron filling of the in-band trap states with drain–source voltage ( V DS ) above a threshold, is proposed to understand this unusual PPC-NPC transform mechanism, which is different from that of any known nanomaterial system. This finding exhibits potentials for developing devices such as photodetectors, optoelectronic switches, and memories.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Xiaobin Liao,Xingji Bai,Huan Qi,Fei Li,Baoling Yuan
N-nitrosodimethylamine (NDMA) has recently been discovered to generate from daminozide (DMNZD) during ozonation . Moreover, its formation is affected by the presence of bromine ion (Br − ) in water, but the mechanism is still unclear. In this study, the effect of Br − on NDMA formation from DMNZD during ozonation at various oxidation conditions (ozone dosages, pH) and distinct water parameters was studied. In addition, the transformation pathways with/without Br − were determined. The results demonstrated that low levels of Br − promoted NDMA formation from DMNZD during ozonation. When Br − dosages increased from 0 to 1 μM, the concentration of NDMA augmented from 138 to 195.5 μg/L. However, when Br − concentration raised to 100 μM, NDMA amounts dropped to 80 μg/L. Increasing pH can raise the ratio of deprotonated DMNZD no matter with or without Br − , and promote its reaction with O 3 molecular to achieve the maximum NDMA formation at pH = 7. The amounts of NDMA decreased dramatically (from 155 to 74 μg/L) when HCO 3 – dosages increased from 0 to 160 μM with 0.1 μM Br − , however, its concentration increased remarkably (from 155 to 225 μg/L) with increasing SO 4 2− (from 0 to 20 μM). Low levels of HA (0.1–0.2 mg/L) boosted NDMA formation while relatively abundant of HA (≥0.4 mg/L) suppressed its formation. In addition, the presence of NOM inhibited NDMA formation from DMNZD during ozonation no matter Br − existed or not. Based on the results of LC/MS/MS, GC/MS and IC-MS, the transformation pathways of DMNZD with/without Br − during ozonation were proposed. This study provided new insights into the role of Br − on NDMA formation from typical amine compounds during ozonation.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2016
·
IF 2.74
Yong Zhou,Yongli Huang,Zengsheng Ma,Yinyan Gong,Xi Zhang,Yi Sun,Chang Q. Sun
A combination of the differential Raman spectrometrics and contact-angle measurements has enabled resolution of the hydrogen bond (HB, O:H O) relaxation and molecular dynamics in the NaX hydration shells. Observations suggest that the aqueous ions create each an electric field to form the hydration shells through O:H O bond elongation and polarization. The ionic polarization shares the same, and even stronger, effect of molecular undercoordination that shortens the H O bond and stiffen its phonon , and meanwhile, the O O Coulomb repulsivity lengthen and soften the O:H nonbond with an association of polarization. O:H O bond electrification raises not only the structure order of molecules and the viscosity in the hydration shells but also the skin stress and thermal stability of the solution. Exercises not only deepen our insight into the salt solute-solvent interaction involved in the Hofmeister series in terms of O:H O bond electrification but also provide a powerful means quantifying the dynamic, local, molecular-site-resolved information regarding the O:H O bond cooperativity in aqueous solutions.
研究领域:
物理化学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jun Cai,Yibing Xie,Chong Ma,Xueqian Wang,Langlang Wang,Ping Ning,Yixing Ma
Photocatalytic oxidation of gaseous heavy metals is an efficient approach to alleviate energy crises and environmental pollution. In this study, a novel two-step solvothermal method was designed to synthesize reduced graphene oxide (rGO)-modified bismuth oxyhalide (BiOX, X = Cl, I, Br) nanosheets. The modification of rGO led to the significant enhancement in the specific surface area of BiOX nanosheets, reduction in the bandgap, improvements in the light absorption range and intensity, acceleration in the photogenerated carrier separation rate, and reduction in the photogenerated electron − hole complexation. Furthermore, both O 2 – and OH were demonstrated to be active species in the reaction. Owing to these achievements, all samples displayed significantly improved photocatalytic performance. Furthermore, the rGO-modified samples exhibited excellent stability and maintained the highest mercury removal efficiency after several cycles. However, the samples prepared in this research displayed a high level of moisture resistance. These characteristics of BiOX-based materials make them potential candidates for the photocatalytic removal of heavy metals from industrial waste gases.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Hongyuan Zhao,Youchao Wei,Yameng Chen,Caiping Liu,Feilong Jiang,Yongsheng Liu,Maochun Hong
All-inorganic Pb-free halide perovskites have recently received extensive attention due to their unique structures and optoelectronic properties. However, the realization of pure-blue emitting perovskite nanocrystals (NCs) with satisfactory stability and rational interpretation for their corresponding self-trapped excitons (STEs) emissions remains an arduous task. Herein, a modified hot-injection method is proposed to prepare a new family of zero-dimensional (0D) Cs 3 ZnX 5 (X = Cl, Br) perovskite NCs with pure-blue and sky-blue photoluminescence (PL) emissions. Benefitting from the 0D tetragonal-phase structure, the Cs 3 ZnX 5 NCs possess outstanding long-term stability in ambient air conditions. We employ the experimental results and first-principles calculations to confirm that the blue STEs emission of Cs 3 ZnX 5 NCs is dominated by the halide vacancies (V X ) in [ZnX 4 ] 2- tetrahedra. Our findings not only provide a simple and valid method to control the synthesis of blue-emitting 0D Zn-based perovskite NCs, but also clarify their underlying PL mechanism.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Wenzhi Wang,Liwei Wang,Shuo Song,Xinxin Guo,Hongyu Liu,Guangqiang Liu
All inorganic perovskite quantum dots (PQDs) have been studied extensively because of their excellent photoelectric properties. However, its poor stability and lead toxicity limit its practical application. At the same time, the complex synthesis conditions of the hot injection method also limited the preparation of large quantities. Here, we have successfully synthesized Mn-doped CsPb(Cl/Br) 3 PQDs with excellent thermal stability at room temperature by a simple supersaturation crystallization method. The synthesized Mn-doped CsPb(Cl/Br) 3 PQDs has good homogeneity and crystallinity. Meanwhile, Mn-doped CsPb(Cl/Br) 3 PQDs maintains the same crystal structure as CsPb(Cl/Br) 3 PQDs. Importantly, it was found that the activation energy of CsPb(Cl/Br) 3 PQDs after manganese doping increased from 65.1 meV to 222.8 meV through the high and low temperature PL test of 80 K–500 K. The crystal structure of CsPb(Cl/Br) 3 PQDs is more stable due to the introduction of manganese ion, and the thermal stability is significantly improved. In this study, manganese doped CsPb(Cl/Br) 3 PQDs with good crystallinity and thermal stability was rapidly synthesized by a simple supersaturation crystallization method at room temperature, which opened up a new way to improve the stability of PQDs and explore other non-toxic metal elements to replace Pb 2+ .
研究领域:
材料科学
·
纳米技术
·
化学
·
物理学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 30
·9167-9174
·
IF 6.641
Chong Li,Baojun Ding,Lijing Zhang,Kepeng Song,Shengyang Tao
Organometal halide perovskite nanocrystals have received extensive attention as a high-performance photoelectric conversion material. However, the perovskite nanocrystals prepared by the traditional batch reactor have uncontrollable size and optical properties, low utilization of raw materials, and complicated purification treatment. In this paper, a flow microreactor is designed with the assistance of finite element analysis and realized the continuous synthesis of CH3NH3PbX3 nanocrystals with a 100% yield. The average size of the prepared nanocrystalline grains is as low as 3.9 nm without any purification step. The prepared nanocrystals have narrow-band emission characteristics (the full width at half-maximum is down to 18 nm), and the quantum yield can reach 76.9%. It is also possible to prepare CH3NH3PbX3 (X = Br, I) nanocrystals covering different emission wavelengths in the visible light region by this method. The coating of a polystyrene film improved the stability of the perovskite nanocrystals. The flexible hybrid film is applied to modify a LED device, and a white LED luminescence spectrum is obtained.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
化学工程
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2021
·
IF 5.165
Mao-Yin Ran,Sheng-Hua Zhou,Wenbo Wei,Bang-Jun Song,Yong-Fang Shi,Xin-Tao Wu,Hua Lin,Qi-Long Zhu
Inorganic chalcohalides are attracting a tremendous amount of attention because of their remarkable structural variety and desirable physical properties. Although great advances have been made in recent years, functional inorganic chalcohalides with two-dimensional neutral layers are still rare. Herein, two novel chalcohalides CdSnSX2 (X = Cl or Br) with high yields were obtained by reacting CdX2 with SnS using a traditional solid-state method at 823 K. Both of these chalcohalides adopt orthorhombic space group Cmcm (No. 63) with the following structural values: a = 4.014(4)–4.064(2) Å, b = 12.996(2)–13.746(3) Å, c = 9.471(2)–9.621(2) Å, V = 494.1(8)–537.5(2) Å3, and Z = 4. The prominent architectural feature is the unique two-dimensional [CdSnSX2] neutral layer consisting of composite [CdX2] and [SnS] sublattices that are connected alternately through the Cd–S–Sn bonds along the ac plane. The [CdX2] sublattice consists of a single octahedral chain of Cd-centered [CdX4S2] groups sharing cis-X edges, while the [SnS] sublattice consists of a bend-shaped chain of unusual [SnS2X2] units sharing vertices of S atoms. Significantly, each CdSnSX2 form (X = Cl or Br) shows high visible-light-induced photocatalytic activity for rhodamine B degradation, which is ∼7.0 times higher than that of nitrogen-doped TiO2 (TiO2–xNx) under the same experimental conditions. This discovery enriches the categories of inorganic chalcohalides and provides more choices of candidate materials for photocatalytic applications.
研究领域:
无机化学
·
材料科学
·
光催化
·
固态化学
✓ 已验证
DOI
高影响因子
Science China-Technological Sciences
·
2020
·Vol. 64
·期 1
·91-97
·
IF 2.302
Cao Yong,Li Jian,Yang Peng,Wei KaiYuan,Ma ShiPing,Zhang XiaoQiang,Wu MeiFen,Liu XiaoJiang,Cui YanHua,Wen ZhaoYin
NiCl 2 with high theoretical voltage and thermal decomposition temperature attracts much attention as cathode material for thermal batteries with the requirement of high power density, high energy density and long work time. Unfortunately, the practical utilization of thermal batteries with NiCl 2 cathode is limited by their poor electrochemical performance under large current, even with the conventional LiF-LiCl-LiBr all-lithium molten salt electrolyte which proposes ultrahigh lithium ion conductivity. In this work, an unexpected ionic exchange reaction between NiCl 2 and LiBr in LiF-LiCl-LiBr was found, which would be the main reason for the poor electrochemical behavior of thermal batteries with NiCl 2 cathode and LiF-LiCl-LiBr molten salt. On this basis, LiF-LiCl-Li 2 SO 4 , another all-lithium molten salt free of LiBr, was investigated as the new electrolyte for NiCl 2 cathode. For the single cell of Li(Si)/LiF-LiCl-Li 2 SO 4 /NiCl 2 , a discharge capacity of 377 mA h g −1 (with a cut-off voltage of 1.2 V) was achieved with large current density (500 mA cm −2 ) applied at 520°C, which is almost twice of that of Li(Si)/LiF-LiCl-LiBr/NiCl 2 (190 mA h g −1 ) at the same conditions.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）